lies to the south of the town Originally known as Maghmakeer as early as the 14th century, the town eventually came to be known after the Coll (or Cole) family who built
Ballincollig Castle during the reign of
Edward III, before selling it to the Barrett family in either 1468 or 1469. The castle was taken from Andrew Barrett by rebels in 1641, but they were expelled by English Parliamentary forces under
Murrough O'Brien, Earl Inchiquinn, in 1645. It was garrisoned for
James II in 1689, during the
Williamite war in Ireland, then remained unoccupied after his defeat, and fell into decay. The
Ballincollig Royal Gunpowder Mills were opened in 1794 by Charles Henry Leslie, a prominent Cork businessman. Eleven years later, the mills were bought by the British, who were preparing for
war with Napoleon, and the barracks were built to protect the supply of gunpowder. It was one of the largest gunpowder mills in the
British Isles. In 1837, the mill employed several hundred workers, and by 1880, Ballincollig was one of the largest industrial establishments in Cork, with the mill employing many men and boys from the area. With the closure of the Gunpowder Mills in the early 1900s, Ballincollig became little more than a small village on the road from Cork city to the larger market town of Macroom. The
3rd Royal Munster Fusiliers (Reserve) Battalion were stationed there during the Great War. Other Regiments stationed in the Barracks before it was decommissioned were 1st Field Artillery Regiment and 8th Field Artillery Regiment (
FCÁ). The recently decommissioned Murphy Barracks was a major source of employment. In the 1970s, Ballincollig developed as much more of a satellite town, with many housing developments constructed around the old village, and housing people who worked in Cork city or its suburbs. This expansion continued through the late 80s and 90s. Consequently, the town's population has risen dramatically, particularly with the westward expansion of the town and Ballincollig grew to be largest town in the county. In 2019, as part of the boundary expansion of Cork city, Ballincollig was
brought within the administrative area of Cork City Council. ==Religion==